lucene 入门实例

1、建立索引

/**
* 建立索引
*/
public void index(){
IndexWriter writer=null;
try {
//1.创建Directory:创建索引的保存地址
//  Directory directory=new RAMDirectory();//建立在内存中
Directory directory=FSDirectory.open(new File("E:/lucene/index01"));

//2.创建IndexWriter, 是用来操作（增、删、改）索引库的
IndexWriterConfig iwc=new IndexWriterConfig(
Version.LUCENE_35,
new StandardAnalyzer(Version.LUCENE_35));
writer=new IndexWriter(directory, iwc);

//3.创建Document对象
Document doc=null;

//4.为Document添加Field
File f= new File("E:/lucene/example");
for(File file:f.listFiles()){
doc=new Document();
doc.add(new Field("content", new FileReader(file)));
doc.add(new Field("fileName",file.getName(),
Field.Store.YES,Field.Index.NOT_ANALYZED));
doc.add(new Field("path",file.getAbsolutePath(),
Field.Store.YES,Field.Index.NOT_ANALYZED));

//5.通过IndexWriter添加文档到索引中
writer.addDocument(doc);
}
} catch (CorruptIndexException e) {
e.printStackTrace();
} catch (LockObtainFailedException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}finally{
if(writer!=null)
try {
writer.close();
} catch (CorruptIndexException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}

2、搜索

/**
* 搜索
*/
public void searcher(){
try {
//1.创建Directory：去哪里搜索
Directory directory=FSDirectory.open(
new File("E:/lucene/index01"));

//2.创建IndexReader
IndexReader reader=IndexReader.open(directory);
//3.根据IndexReader创建IndexSearcher
IndexSearcher searcher=new IndexSearcher(reader);

//4.创建搜索的Query
//创建parser来确定要搜索文件的内容，第二个参数表示搜索的域
QueryParser parser=new QueryParser(
Version.LUCENE_35,
"content",new StandardAnalyzer(Version.LUCENE_35));
//创建Query，表示搜索域为content中包含java的文档
Query query=parser.parse("java");

//5.根据searcher搜索并且返回TopDocs
TopDocs tds=searcher.search(query,2);
System.out.println("总共有【" + tds.totalHits + "】条匹配结果");

//6.根据TopDocs获取ScoreDoc对象
ScoreDoc[] sds=tds.scoreDocs;

for(ScoreDoc sd:sds){
//7.根据searcher和TopDocs对象获取Document对象
Document d = searcher.doc(sd.doc);//sd.doc:文档内部编号
//8.根据Document对象获取需要的值
System.out.println(d.get("fileName")+
"["+d.get("path")+"]");
}
//9.关闭reader
reader.close();
} catch (CorruptIndexException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (ParseException e) {
e.printStackTrace();
}
}